Optical testing apparatus



Aug., 1933.

H. G. FANK OPTICAL TESTING APPARATUS Filed Sept. 18 1950 3 SheeiS-Sheet l G9 3x O was @nvm ll'r O a@ l @D O Q@ b ll 217 1| O /Bb :1*-

I L E Baa @@0@ 9 55 5D( a@ 55d b3 3 o bb w 59 6T O 0 @a and *ra 5 T B0 kr1 NLE-im .Ih o *Q :f1- g? 35 o A O 55d C) 67 `I i @up lll Tir-"- '3,.- 0 n 59-Vv Il l :i 88 xl 9 l o@ l if, Z 45 l P |11 v a ne 65 6 5 q Q im Ilzl HawlaGwrfhk mvaNToR' WAL@ EM ATTORNEY Aug. Pi/33. H. G. PANK Y OPTICALV TESTING APPARATUS Filed Sept. 18, 1930 3 Sheets-Sheet 2 H am) George Pon k \N\JN TOR 9cm ATTORNEY Aug'. 1, H. G. PANK OPTICAL TESTING APPARATUS Fied Sept. 18. 1950 5 Sheets-Sheet 3 Marchi (1am/9e Punk 50 |N v NTO-R Patented Aug, I, 1.933

intriso STATES 1,920,428 oPTICAL Tss'riNG APPARATUS f Harold George Pauli, Adelaide, South Australia,

` Australia Application @september is, 1930, serial No. 482,755,and in Australia October '7, 1929 is claims.

This invention relates to optical testing apparatus. The more important part of the appa-l ratus consists of. what may be termed a visual' reactometer. In addition, the apparatus, vincludes means foi` testingvisual acuity and color vision.

A serious defect of the ordinary method of testing visual acuity by means of the Snellen chart is that the time factor isnot controlled. In other` words, the eyes are givenso long a period of observation that the test is largely 'vitiated by the accommodation factor.k .In effect, this means that the eyes are given suicient time to accommodate to an apparent visual acuity that is not correct. Y

ln View of the foregoing, apparatus has been proposed in which an illuminated split circle or similar convenient device has been momentarily exposed by inea-ns of a photographic shutter. l By e@ the use of the foregoing, the accommodation factor is eliminated, as the subject must observe in the limited time vthe position of the split in the circle, or other prominent feature. n such apparatus, the subject has been required to describe k the position of the split in the circle in relation to various points of the compass, that is to say,

north, east, south, north-east and so on. Suchl arrangement of describing the effects seen is unsatisfactory, because many persons are inof describing the position, although uns' doubtedly they see it without difliculty.

The present apparatus includes meansr for effecting the foregoing purpose, but it does so in an improved manner. In addition, graphical are available tothe subject-to enable recording oi the impression received without possibiity of errer through'misunderstanding Another factor that can be investigated by means of this apparatus is what may be termed e@ the time lag or hysteresis between the instant of perception andthe recording of such perception. ln many occupations and circumstances it is very important that but a short space of time should elapse sees an object and is able to take measures to act on the perception which is recorded. Thus, in di 7ing an automobile, it is not much use if the driver clearly sees an obstacle but is unable to react in a short space of time tothe perception "0 which is recorded, In a similar manner, workmen operating on fast moving machinery must be able to give a rapid reaction to the percep-` tion of the moving' parts.

The apparatus forming the subject of the pres--` ent invention includes means whereby the time iag above referred to can be measured, and so will permit an accurate determination to be made of the subjects iitness for a particular occupation or the like. l

The apparatus embodying the features so rebetween which the subject clearly ferredto may be termed a visual reactometer. The apparatus however'also includes means for testing color vision. Summarised, the complete apparatus includes means for `the following optical tests:-

(1) .Acuity in contra-distinction to the appar# ent acuity as measured by vthe Snellen chart.

l 2) The time lag between the instant of perception and the recording of such perception.-

(S) Test for color vision. 7o

The nature of the invention will now bereferred to,the split circle being used as a suitable, device for describing the invention.

It comprises broadly two parts, namely, one part positioned. immediately'in front of thev subject, and the other or main part some distance away and incorporating the various exposure and tiine-recording'parts which in lsome parts of the speciiication are referred to as the primary parts, and which include the main setting apparatus which records or veries the observation made by the patient.

The main part of the apparatus includes means for holdingthe split'circles which will be chosen of a size to suit the subject, means for illuminating the split circle, and a photographic shutterA to give any desired exposure, say 0.1.of a second. Included with such apparatus is a dial or plate having, for example, eight equally spaced lamps that can be illuminated under the circumstances subsequently to be referred to. The split circle used for any particular subject is supported vand can be turned tol any desired position by the operator setting the position in'whichy an electrical contact is made in one or other of the positions corresponding to the Avarious positions of the lamps. Functioning electricallyin conf, junction with the button which operates the shutter will be the `timing apparatus. This will conk veniently consistof a continuously movingelec 100 tric motor which, at the instant of operating the shutter, is, through an electro-magnet, keyed on to a recording hand which is thereupon instantaneously caused to rotate in relation to a time-indicating dial. y

The part of the apparatus immediately in front of the subject includes a plurality of metallic contactsA corresponding to the various lamp positions on the other part of the apparatus. These contacts may be of any convenient form. There is in addition provided a iiexible lead terminating in' a metal contact that in operation is to be plugged into or against one or other of the contacts above referred to.

The apparatus is operated as-follows:-

A split circle of a size to suit thepatient is held in position and turned to any position re,- quired. The patient is then told to watch Afor the exposure, and immediately the exposure oc' curs to plug into or against the correspondingly 120 aware that there is an object.

vindicate the limit of his '.tleld of vision, although apparatus, which was set in motion on operating the shutter, is stopped and the time taken by the subject to record the perception will be available. 1fv the subject makes an incorrect contact, the circuits will not be completed, and a lamp will not be illuminated in the far portion of the apparatus.

It will be' obviousv that in testing a patient, a

number of tests will be made, and from the same an averagevaluaboth for correctness of perception and for theftime lag above referred to, can be obtained. v

The value oi the foregoing sequence of tests of central vision` will berenhanced by the following means for testing the subjects intermediate and peripheral fields of vision. Obviously, a subjects vision may be quite satisfactory as far as straightahead objects are concerned, but may be impaired in regard to observing objects towards the periphery of the iield of vision.

To provide a test for such purpose, `provision can be made for having a quadrant member supported on the right and left o the peripheral field of vision to the centre of vision. Supported on the aforesaid quadrants, preferably in sliding relation thereto, will be a member or members provided with an opening facing towards the subject. Supported inside such member will be a split circle or other suitable object, provision being made whereby the split circle can be moved and held in various desired positions in a vertical plane. y i

The split circle is so supported that it is capable of being rotated in a horizontal plane, means such as a weight or spring being provided for such purpose. In consequence, when desired, the split circle can be caused tov rotate, and will therefore appear for short intervals in line with the opening in the member. i

The method of using the apparatus in question will be to slide the member in from an extreme limit beyond the peripheral limit of vision, and a stage will be reached when the subject becomes Such position will it will certainly not indicate that the object is seen with any degree of precision. The member is then slid further along the quadrant and the split circle rotated from time to time until a point is reached when the subject can distinguish not only the nature of the object viewed, but can also see the same with precision in regard to the position of the split in the circle, either when'the circle is stationaryor whilst exposed during movement. Means can be provided, such as by utilizing the plug-in devices previously alluded to, whereby the subject can record his visual impression.

It will be obvious that by reason of the foregoing arrangement, it can be determined whether the subject has a satisfactory vision on the intermediate or peripheral fields.

As previously stated, conveniently incorporated with the apparatus will be means for testing .color vision. This is effected by making each of the lamps on the far part of the apparatus of a different color, and in providing correspondingly colored lamps on that part of the apparatus close to the subject, the latter lamps being, when the visual test is made, all illuminated.

In making the test, one lamp at a time is illuminated on the far portion of the apparatus, and the subject is required to indicate, without necessarily naming the color, which oi such colorsthe illuminated lamp corresponds to regard to the lamps placed in iront of him.

It will obviously be desirable for the colored lamps on the two parts of the apparatus not to be in the same relative positions, v

But in order that my invention may be more clearly understood will now describe the same by vaid of the accompanying illustrative drawings wherein similar numerals of reference are used to denotev similar or corresponding parts, the setting part being referred to as vthe far part, and the recording apparatus as the near part.

In the drawings Fig. l is a front elevation perspectively drawn to illustrate the setting and the receiving or recording parts.

Fig. 2 is a side View of setting apparatus per- `spectively drawn showing position of shutter and illustrating apparatus on the far part.

Fig. 3 is a side View of recording apparatus perspectively drawn and provided with rotating screen carrier for width of vision test in the near part.

Fig. i is a planof Fig. 3.

Fig. 5 is a sectional View of setting shutter mechanism in the rar part.

Fig. 6 is a sectional side elevation or" time recording mechanism on far part.

'l is a rear view oi operating mechanism forv width of vision test on near part.

Fig. 8 is a cross section of Fig. 7.

Fig. 9 is the wiring diagram of the associated parts.

In the drawings the supporting standards ol the far part and the near part of the mechanism are indicated at 1 and 2 respectively. At the top of the standard 1, I mount a frame 3, the arms oi which are provided with a lug i which forms a horizontal axis for setting the whole of the upper mechanism at any desired angle, and is provided with a locking clamp 5.

The mechanism for sight testing comprises a shutter 6 consisting o1" a band of fabric with a transverse opening 7, the ends of the fabric being secured to rollers 8 of type in common use in photographic cameras.`

The rollers khave the usual setting and timing mechanism and are furnished with a press button release 9 also of usual type with which I also associate an electric switch 10 shown in Fig. 9.

` Behind the shutter is a rotatable disc 11 upon` rthem in engagement, the square 18 on the end of thershaft 14 being adapted to register with a recessed square 19 of the disc 11.

The `handle 12 forms a switch arm engaging one of a series of eight contacts 20 supported in rio front disc 22 are preferably of insulating material.

Immediately in front of and covering the outer surface of the annular face of thedisc 22'I rotatably mount an annular plate. 24 which is fitted with capstan bars or projections 25'whereby it can be rotated. This annular plate has a series of apertures 26 which register with the perforations in lfront of the lights 23.

These kapertures are filled with colored glass, there being one distinctive color for each aperture.

There are, or may be, intermediate openings 26a likewise lled with colored glass, the colors being diiferently arranged. The annular ring is maintained in its proper position by thel bearings 27. f v

Above the annular disc I mount a pivoted frame 28 which supports a smaller rotatable disc 29 likewise having a series of apertures therein, each of which may in turn be brought into alignment with the highest aperture of the main disc.

One set of these holes which are indicated at 38 is covered with glass of various colors so as to enable a patient to be tested with regard to intermediate colors which can thus be obtained by bringing two different colors in frontof a light. The other group of apertures 31 are of diminishing size so as to produce the eifect of lights at a corresponding series of greater distances.r

The centre portion of the disc 22 is characterized by forming therein an aperture 33 which is immediately opposite the split circle, and at each side of this aperture I mount a lamp y34 to illuminate the-split circle, reflectors being added to direct the light.

A multiple switch is indicated at 35, and this comprises three sets of four switches 36, 37 and 38 as indicated in wiring diagram Fig. 9. These switches are mechanically connected to" one handle 39. 'Beneath this switch is a box 40 within which there is a motor 41, the spindle of which operates `worm gearing 42, thus rotating the spindle 43, the other end of which terminates within the field of an electromagnet 44 and is constructed of soft iron to form 'an armature.

Adjacent to the end of vthis spindle is another spindlee which is rotatably and slidably mounted in a bearing 46. f

Theend of the spindle 45 is kept away from the end of the spindle 43 by `a spring 47 until kthe field of the magnet is energized,` whereupon the soft iron end of the spindle 43 is magnetized,l

drawing and holding the end of the spindle 45 against it.

Upon the end of thespindle 45 I mount a hand -or pointer 4s behind which is a. graduated dial` 49. The motor is governed by the usual means to rotate at a constant speed, and thefmechanism is designed to impart one rotation of the hand per second.

The box also contains a transformer and a drop shutter switch 5l, and a series of electrically controlled circuit breaker switches 52.

Referring now to the front standard 2, it will be seen .that I provide constructional mechanism which may be regarded as a repetition 4or counterpart of some of the mechanism which ismou'nted on the back standard. There is a secondary annular disc 53 having eight circumferential holes, an annular ring 54 likewise furnished with holes 55 and 55a, and capstan bars 56 for, ro-` tating the ring, and a series of eight lamps `57, all these parts being substantially the same as the parts on the standardl, except that the disc 53 is fixed upon a tubular shaft 58 which is carried by bearings 59 on the secondary standard 2.

Attachedto the shaft 58 is a ring 60 having eight slots adapted to be 'engaged by a locking pawl 6l the pawl being pivotally mounted on the bearing 59. Adjacent to the eight lamps 57 situated at the cardinal points I form a corresponding number of cone mouthed sockets 62', each being partially surrounded by a small shield 63 connected thereto, the sockets being adapted to accommodate a jack 64 on the end of a flexible cord 65.

Instead of the central aperture 33 this` part of the mechanism has an Aaperture 66 registering with the tubular shaft 58 which is directed to a moving exhibit to concentrate the. attention oi' the patient for the width of vision test. It consists of a rotatably mounted drum 67 supported on a vertical spindle 68, its periphery being fitted with illustrations of motor Vehicles or illustrations of other traic, so that when the drum is rotated by a motor 69 these moving objects will appear to pass before the patient and hold his attention, there being a lamp 70 to illuminate the picture. f

A vertically supported radial frame 71 is rotatably mounted by means of a sleeve around the tubular bearing 58, Within the xed bearing 59, andv may be locked at any angle by 'means Upon the radial arm I mount a sliding boxv 80. This box contains a disc 74 upon which the split circle is displayed, the circle being rotatably mounted in a frame 75, lthe frame being slidably mounted on the rod 76. The disc is rotated by` a handle 77 and `held infplace by a spring arm 78 which engages one of the setting holes 79. The box has an opening 80a in the centre of its front face through which the slotted circle can be viewed when the frame 75, and consequently the disc 74, is adjacent to the centre of the box.

The slotted circle is caused to pass across the aperture by means of a pair of small toothed wheels 81 and 82 which are mounted upon and carried by the frame the lower toothed wheel 8l is operated by a flexible driving .connection 83 to the motor 69. The upper toothed wheel 82 engages a rack 84 extending across the box, both ends of the rack being bent back and pivoted to the rod 76, there being an extension 85 which projects through a slot 86 inside ofthe box'.

To keep the patient at a suitable distance from the instrument I provide an'adjustable chin rest 87 which is hinged to the `secondary standard 2 and. may be elevated to any suitable angle and is clamped on a quadrant plate 88, the standard being also adjustable by telescopic movement. v

A multiple switch is indicated at 89, and this .comprises two sets of four Vswitches 90 and 91 as a constanty speed, means including an electromagnet normally out of operation for connecting said pointer and power means, an electric circuit joining said lamps, electrofmagnet and current source, means for releasing said shutter to ei:- pose said plate to a patient for a limited time, said means completing said electric circuit and causing the energization or" said electromagnet to thereby couple said power means and pointer, a second support, a second set of lamps arranged on said support Vat points corresponding to the arrangement of said iirst set of lamps, said second support having sockets leading to said lamps, means for electrically connecting a lamp of one set ina circuit with a lamp of another set, a plug adapted to be inserted by the patient into the socket of a lamp corresponding to that indicated by said direction marker to thereby complete the circuit between said lamps and cause their illumination, no circuit being completed if the plug is not inserted in the proper socket, and means operative upon the completion oi said circuit to break said iirst circuit and detach the power means from said pointeri 6. An opticaly testing apparatus `comprising a support, a circular plate having a central aperture mounted on said support, a disc having a split circle rotatably mounted on said support so as to be obse ved through the aperture in said plate, a shutter adapted to normally cover said aperture, a set oi lamps arranged atv fixed points around the circumference ci said plate, means for rotating said disc to cause the split circle to point to one of said lamps,`means for releasing said shutter toveXpose said disc to a patient for a limited periodof time, time indicating means on said support, electrical means for operating time indicating means, said electrical means being controlled by the means for releasing said shutter, a second'support, a plate on said suplport bearing a set of lamps arranged in posin tion to correspond to the arrangement of the lamps on said iirst support, said plate having sockets leading to said lamps, electric connections for joining a lamp of one set to a corresponding lamp of another set, a plug for insertion by the patient into a socket of va lamp corresponding to the lamp indicated by said split circle to comi plete the circuit between said lamps and cause their illumination, no circuit being completed if the patient inserts the plug in the wrong socket, and means operative upon the completion of said lcircuit to stop said time indicating means.

'7. In an optical testing device, a support, a case mounted on said' support, a bearing in the rear wall of said case, a disc having a direction indicating marker on its front face, a stud on the rear face of said disc mounted in saidloearing, a socket in said stud, a rotatable radial shaft journalled in the support opposite said bearing, ay

handle slidably mounted in the journal ofrfsaid shaft, one end of said handle having an end adapted to be received in the socket of said disc,4

a spring retaining said end in said socket, a

clutch for releasably joining said handle and` shait whereby to effect rotation of said dise, and a releasable shutter in said case in front of said disc.

8. In an optical testing apparatus, a fixed cirn cular plate having a central aperture therein, a plurality of lamps secured to the rear of said plate, said plate having va plurality of` openings adjacent said lamps, an annular plate rotatably mounted on said xed plate, said second plate having a plurality of apertures corresponding to the apertures in said xed plate and additional apertur s therebetween, the apertures in said rotatable plate bearing glass plates of varying color.

9. A device as recited in claim 8 including a frame pivoted to the top oi said fixed plate, a disc rotatably mounted on said frame, said discA having a plurality of sets of apertures, each of which is adapted to be brought into alignment with the upper-inost aperture of said iixed plate, the apertures of one set bearing colored glass plates and the apertures of the other set having diameters of varyinsT size.

20.n an `optical esting apparatus, a device for recording the time o exposure of an object to a patient comprising, an object 'to be viewed, means for exposing said object, a graduated dial, a 'support for dial, a dial pointer, a spindle slidably journalled in said support and attached to said dial, a second spindle of soit iron opposite nrst spindle and having one end connected to a source of power, a socket on the end of said second spindle facing said first spindle, spring means for maintaining said spindles out of contact, an electromagnet surrounding the socketed end of said second spindle, and electrical connections controlled by the ineans for exposing said object to energize electro-magnet and thereby cause a couplingof said spindles.

il. in an optical testing device, a support, a centrally apertured disc on said support, a plurality of lamps ysecured to the back of said disc, an `object to be viewed located behind said cer ral aperture, disc having a plurality of apertures said lamps, an annular plate rotatably mounted on said disc, said plate having rality of apertures bearing colored glass, yain of apertures overlying the apertures in said a second support, a-hollow shaft, a disc on said shaft, a plurality ofk lamps on said disc, said disc apertures corresponding to those on said first an annular plate rotatably mounted on said dise and having apertures arranged like ape ires in rst annular plate and bearing colei ed glasses and means for illuminating said lamps.

12. A device as recited in claim il including a rotatable drum secured to the second support adjacent the inner end of said hollow shaft and bearing markings adapted to be seen through said shaft, a radial arm rotatably mounted on said shaft, means ior locking the arm at a desired angle, sliding means on said arm containing an object to be viewed and graduated means on the arm for recording angle oi vision.

13. In an optical testing device, means for measuring the angle of vision comprising a supmeans fixed thereon to cause the patient to :ocus his eyes to the :j: t, arm rotatably lmounted id support, a sliding box on said radial :l box having an aperture in the front thereof, a disc bearing marking indicia rotatably mounted ins 1 box so as to be observed through ape; ure, means for ro tating said disc, means -for locking the disc in position, means for moving the disc from one end of the bos: to the other and ca brations on said radial HAROLD GEGRGE PANK. 

